Case Study
Limpopo Province, South Africa
The Lannex chromite mine, a key part of Samancor Chrome’s operations within the Bushveld Igneous Complex in South Africa, significantly contributes to the country’s chromite ore and ferrochrome production.
This case study outlines the challenges and solutions encountered in its operation.
At the Lannex Mine, a surface processing plant concentrates chromite ore from various mines in the Steelpoort area.
With a workforce of 600, the plant’s operations heavily depend on water recirculation systems.
However, the processed water, rich in solid materials, posed a challenge for reusability, leading to the use of sequential settling sumps for solid sedimentation by gravity.
The settling sumps at Lannex were rapidly filling with solids every two weeks, necessitating frequent and labor-intensive cleaning. This process required 8 workers manually clearing the sumps and led to a 12-hour plant shutdown for every cleaning session, during which only one-third of the sump system could be addressed. The abrasive and dense nature of the chromite slurry further complicated the task.
To tackle the sump cleaning challenge, Lannex Mine consulted with the Goodwin submersible pump team for an effective solution.
They recommended the Goodwin 100 ANZE pump, renowned for its proficiency in managing heavy slurries. The team explained that pump’s ability to efficiently clear settled solids from the sump would require additional water adding to the sump to allow for the material to be pumped out, as whilst it has been likened to a vacuum cleaner by those who have witnessed its operation, it is a pump and required water to operate.
The Lannex mine strategically placed a Goodwin 100mm ANZE submersible slurry pump, featuring a 100mm discharge and a powerful 30kW motor, at the heart of its settling sump, complete with a control panel. To optimize the pump’s performance in handling the slurry, which had a density of 1.6kg/l, a modest amount of water was added to thin the settled solids.
This strategic move drastically enhanced the sump cleaning process, allowing a single worker to remove all solid material in a mere 4 hours, thus boosting both efficiency and safety.
Following Lannex’s lead, the nearby Samancor Tweefontein concentrator also adopted this pump for their sumps. The pump’s low usage and minimal maintenance needs – only one wet-end replacement over three years – highlighted its reliability and effectiveness, culminating in a significantly streamlined process for Lannex Mine, cutting labor and reducing cleaning time from 12 hours to just 4.
